2025/12/15 by Ben-Yang Zhu, Yun-Feng Liang, Zhu, Ben-Yang +3
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2512.13261
openalex publication_date 2025/12/15 · openalex created_date 2025/12/17 · openalex updated_date 2026/07/28
A recent analysis of pulsar timing data has reported evidence for a massive (∼ 6 × 107 M\odot) dark matter subhalo located only ∼ 0.8 kpc from Earth. This candidate implies an exceptionally large J-factor of ∼ 1023 \rm GeV2 cm-5, exceeding that of known classical dwarf spheroidal galaxies by orders of magnitude and rivaling the Galactic Center. In this work, we utilize more than 17 years of Fermi-LAT data to search for gamma-ray emission from this subhalo. We identify a tentative excess in the region with ambiguous origin. Adopting a conservative strategy, we retain this excess without modeling additional astrophysical components, treating it instead as unmodeled background to derive upper limits on the dark matter annihilation cross-section for the bb and τ+τ- channels. Despite this conservative treatment, the resulting limits remain stringent due to the exceptionally large J-factor. Subject to the dynamical confirmation of the subhalo, these constraints are potentially orders of magnitude stronger than those obtained from combined analyses of dwarf spheroidal galaxies and blind subhalo searches.